Drill support



y 1940. A. M. STONEIIRI 2,207,231

DRILL SUPPORT Filed Dec. 5, 1938 Z0 /6 ,-i id ATTQiNEYS Patented July 9,1940 UNITED STATES DRILL SUPPORT Arthur Merrick Stoner, West Hartford,Conn.,

assignor to The Jacobs Manufacturing Company, Hartford, Conn., acorporation of Connecticut Application December 5, 1938, Serial No.243,999

5 Claims.

This invention relates to improvements in drill supports.

Its object is to provide a simple and inexpensive attachment for drillchucks to increase the utility of such chucks and to protect the drills.Drills, especially those of small diameter, are easily bent and brokenand an object of this invention is to overcome this difiiculty.

Another object is to provide an arrangement to preventing marring of thedrilled material.

A still further object is to provide a device which is longitudinallyadjustable in order to support properly drills of different lengths.

In the drawing,

Fig. 1 is a sectional side elevation of a chuck shown in my copendingapplication for patent, Serial No. 218,111, filed July 8, 1938, with adrill support, which is also shown in said application, attachedthereto, the latter being shown in elevation, (not sectioned);

Fig. 2 is a sectional end view of some of the parts shown in Fig. 1, thesection being taken on the line 2-2 of the latter figure;

Fig. 3 is a front elevation of the drill support shown in Fig. 1;

Fig. 4 is a sectional side elevation of a modified form of drill supportwhich includes a longitudinally adjustable bushing and means for holdingit in a desired adjusted position;

Fig. 5 is an end elevation of a locking ring, one of the parts shown inFig. 4; and

Fig. 6 is a sectional side elevation of a modification in which a partof the chuck forms a part of the drill support.

The chuck shown in Figs. 1 and 2 comprises a substantially cylindricalbody l having a transverse face |2 is an arbor tapered to fit an axialhole in the body and adapted to fit the driven socket of a machine tool,such as a power drill. 3 is an annular groove near the rear end of thebody in which is a spiral spring I 9.

Three post holes I! are drilled into the body from its outer face. Theseare equally spaced angularly and are at equal distances from the centralaxis of the body. Between them are tapped holes I8.

20 is a sleeve rotatably supported on the body I0. At its forward end isan internally toothed flange 2| which overlaps the outer face ll of thebody. The ends of the spring l9 are attached to the body l0 and to thesleeve to cause the sleeve to rotate on the body in a clockwisedirection as viewed from the rear of the chuck (Fig. 2). It may berotated in the opposite direction by hand, by the operator grasping theouter surface of the sleeve which is fluted as shown, to

facilitate such operation.

Posts 30 are fitted into and seated upon the bottoms of the holes IT.The outer end 33 of each post is of reduced diameter and forms ashoulder 34.

Pinions 36 fit the posts 30 rotatively. These are in mesh with the teethof the flange 2| of sleeve 26. They are of sufiicient thickness toextend, when seated on the face ll of body l0, beyond the flange 2|, asshown at 36a in Fig. 1.

4D designates the clamping jaws. These have cylindrical bores 4| whichfit the posts 30 with interposed rollers 42. Each jaw has a body witheccentric ribs 44. The contour of the'ribs 44 is alike on all of thejaws, but they are spaced differently on each jaw, as shown in Fig. 1,so that their edges can be moved together to a common axis, as shown inFig. 2.

From one end of each jaw, a row of crown teeth 41 concentric. with thebores 4| projects. When assembled these teeth fit between the parts 36aof the pinion teeth which extend above the rim teeth 2|, as shown inFigs. 1 and 2.

50 is a cover plate which is provided with clearance holes for thepinions 36 and the teeth 41. I'his lies on the front surface ofthe rimflange in the space between it and the lower ends of the body portions43 of the clamping jaws.

52 is a clamping plate having perforations through which the ends 33 ofthe adjusting posts extend. This clamping plate rests on the shoulders34 of the posts. It is held in place by screws 53 which pass through itand into engagement with the threaded holes I! in the body I.

The central bore of the clamping plate 52 is threaded to receive theboss 6| of a drill support 63 which projects forwardly from the clampingplate and has a central bore 32 to receive a drill. Its sides areflattened as at 63 to receive a wrench. The outer end of the support 60is curved as shown at 64 in Fig, 1, so that it will not mar the surfaceof an object being drilled, if it comes in contact with such surface.

The bore 62 is but slightly larger than the drill with which theattachment is to be used and it is obvious that the device will supportthe part of the drill shank which is within it and eifectively preventthat part of the shank from bending or from breaking from lateralpressures.

As it is desirable to support drills of different lengths, I havedevised the adjustable arrangement shown in Figs. 4, and 6. In thesefigures, designates a housing having a threaded boss II which engagesthe threaded central bore of the clamping plate 52 and a flange 12 withflattened sides, (not shown), to receive a wrench. I3 is a cylindricalbore which extends through the length of the housing. The outside of thehousing beyond the flange is threaded, as shown at M.

80 is a cylindrical bushing which is slidable in the bore l3. 8! is acentral drill supporting bore through the bushing. 82 designates aplurality of spaced shallow graaves around the bushing. In one of themis a split ring 83 of spring wire. The ends of the bushing are rounded,as shown at 84.

i is the tubular body of a cap which is internally threaded to fit thebushing threads M. M5 is the end of the cap. This has a central bore tofit the bushing 88 and has a beveled shoulder ii which engages the wirering 83 when the cap is screwed up tightly on the housing 59.

By this simple arrangement the ring is kept seated in one of the groovesand as it projects outwardly from the surface of the bushing, the latteris effectively looked to the housing.

By unscrewing the cap enough to release the engagement of its shoulder Hwith the ring, the bushing may be pushed into the housing as the ring isthen free to expand and will be forced out of the groove in which it isseated. The resiliency of the ring will cause it to contract when themovement of the bushing brings it into alinement with the other grooves,into any one of which it may be locked by screwing up the cap 15.

The clamping plate of the chuck and the housing of the drill support maybe made in one piece. Such a construction is shown in Fig. 5 in which52A designates the part of such a piece which forms the clamping plateand "FDA the part which forms the drill support housing.

Other structural modifications may be made within the spirit and scopeof'this invention and I intend no limitations other than those imposedby the appended claims.

This application is a continuation in part oi my copending applicationSerial No. 218,111, filed July 8, 1938, to which reference has been madepreviously.

What I claim is:

l. A drill support comprising an externally threaded housing having acylindrical bore, a bushing slidably fitting said housing and having anaxial bore, and an internally threaded cap on the housing arranged tolock the bushing to the housing in diiferent positions relative to thehousing.

2. A drill support comprising an externally threaded housing having acylindrical bore, a bushing slidably fitting said housing and having anaxial bore, a plurality of spaced shallow grooves around the bushing, aresilient ring arranged to be seated in said grooves and to project fromthe external surface of the bushing, and an internally threaded cap onthe housing having an internal surface arranged to hold the ring in oneof the grooves.

3. A drill support comprising an externally threaded housing having acylindrical bore, a bushing slidably fitting said housing and having anaxial bore, a plurality of spaced shallow grooves around the bushing, aresilient ring arranged to be seated in said grooves and to project fromthe external surface of the bushing, and an internally threaded cap onthe housing having an internal beveled edge arranged to engage the ringand hold it in one of the grooves.

4. A chuck comprising a body having a front plate constructed witha-central threaded opening and a housing removably screwed into saidopening, said housing having a clearance bore for a drill and projectinga fixed distance from said plate.

5. A chuck comprising a body having a front plate, a housing projectingfrom said plate, said housing having a cylindrical bore, meanslongitudinally adjustable in said bore arranged to support a drilllaterally and to gauge the amount of projection of the drill, said meanscomprising a bushing having an outer cylindrical surface to fit the boreof the housing and a clearance hole for the drill, and means for lockingthe bushing in different adjusted positions,

ARTHUR M'ERRICK STONER.

